Valve rotating device



Sept 1952 R. 'r. DOUGHTY VALVE ROTATING DEVICE.

Filed Dec. 24, 1949 Patented Sept. 9, 1952 AL E ROTATlNG DEVICE RobertT. Doughty, Detroit, Mich., assignor to General Motors Corporation,Detroit, Mich, a

corporation of Delaware Application December 24, 1949, Serial No.134,897

9 Claims (01. 123-90) This invention relates to internal combustionengines and particularly to poppet valve rotating devices therefor. 1 I

It has been appreciated for sometime inthe art that rotation of thevalves during engine operation tends to prevent excessive and unevencarbon deposits thereon with resultant valve sticking and pitting. Whilemany devices for effecting such rotation have been previously proposedthey have not won general acceptance principally because theirconstructionslacked simplicity of design and involved numerous partswith resultant excessive cost of manufacture and uncertainty oftrouble-free operation. In the alternative, various expedientssuch asimprovements in materials and cooling for the valves and valve seatshave been employed to avoid or at least diminish the pitting andsticking problem. However, with the ever increasing power gines the needfor valve rotation is" continually being re-emphasized. and it is theprincipal object of my invention to satisfy this need with a device forthe purpose which is peculiarly adapted for both low-cost manufactureand dependable performance.

This and other objects which will be apparent from a reading of thefollowing description are accomplished by providing a generally annularring member about the valve stem having a helical interengagement withthe valve guide and an. axially engageable clutch surface arranged tocoact with a similar clutch surface on the valve stem. or member carriedtherewith; said annular member having a limited. longitudinal movementrelative to the valvetojpermitengagement and disengagement of the clutchsurface.

'In thedrawingz j I I 1 v I Figure 1 isan elevational View of one formof my; invention shown in its relation to the valve shown in Figure 3.

Figure 5 is a view similar toFigure 3 but showing a further modifiedvalve rotatingdevice incorporating the principles of my invention.

Figured is an enlarged perspective view of a part of the device shown inFigure-5.

demands being made of internal combustion en- 1 20 tained by thecylinder head 2 and a washer 9 fixed by conventional split looks I!) tothe valve stem 4. It will be understood that upward movement of the pushrod in response to force transmitted thereto by the cam causes therocker to rotate counterclockwise as viewed in Figure 1 and drive thevalvestem downwardly in its guide, the spring yieldingly accommodatingthis movement'of theparts and effecting their return to their initialpositions shown as the cam completes its cycle of operation. I I

To effect rotation of the valve during the upward or valve-closingstroke of its reciprocatory movement I have added a member I5 which iscarried longitudinally with the valve but has freedom for a smallamountof lost motion longitudinally thereof during each change indirection of longitudinal movement of the valve. The member I5 isgenerally annular in shape with a cylindrical portion I6 looselysurrounding the val e stem and provided with one or more (preferably atleast two) radially outward extending protuberances or arms I1- Thesearms I! are conveniently formed integral with the cylindrical portion Itas portions lanced out of and bent away from the cylindrical portion I6.The upper end of the valve guide bushing 3 is counterbored as at. I8 toaccommodate the reciprocal movement of the annular member I5 therein.The walls of thecounterbore l8. are helically slotted as at I9 toslidably receive the arms I1 and cam the same rotatively about the axisof the valve stem,

'. therebyryproducing an 1 oscillatory movement of .the member I5 as itreciprocates with the valve. I The upper portion .of the member I5converges toward the valve stem to provide an inwardly taperedclutchsurface 22, and the valve stem is provided oppositely thereof with acoacting inwardly tapered clutch surface 23 terminating up- I wardly inra shoulder v24. I Shoulder 24 serves as an abutmentfor the upper end 25of member I I5 limiting upward movement of member I5 relative to thevalve to an amount suflicient to effect disengagement of the clutchsurfaces 22 and 23. Du ing downward movement of'member I5 relative tothe valve the clutch surfaces engage, there- I by rotatively locking thevalve and member 15 the frictional resistance to sliding movement of thearms 11 in the slots [9, cause the member E to shift longitudinally onthe valve-ste n with 'each change in direction 'of longitudinal movementof the valve. Hence, when the valve starts moving downwardly from itspositionas shown toward valve open position and the member l5 lagsbehind until the shoulder 2d engages the end 25, following whichathemember then moves downwardly'with the valve and rotates in a clockwisedirection (as viewed in plan) about thevalve'stem by reason of-thecamming action of the slots 19 on'the arms ii. The frictionalresistancev'to the sliding movement of these arms in their slotsprovides an upward reactive force acting against the member to maintainitsend 1245 Jin rotative abutting relation with the shoulder 24 and theclutch surfaces 22 and 23 out of'engagement during the continueddownward mover'nent of the valve toward lopen position. Then upon the:valve reaching its lowermost position and starting its upward movementto returnito closed position, the member again lags behind untiltheclutch surface 23 on the stem zrnoves into engagement with 'theclutch surface 22 ;on thememb'er; following which the .membermovesupwardly zwith'the valve and rotates counterclockwiselby reason of thecamming action of the slots E9 on the arms ii. The

yvalve stem nowlbeing 'frictionally locked to the .member'the valve isalso forced to rotate, sufficient slippage occurring between the lowerend lof the spring and the cylinder head or between 'tli'e'u'pper end"of the spring and the retainer washer, or both, forthis purpose.The'frictional forcesresisting the 'slidirigmovement of the arms .H'inthe slots l9 provide a sufficient reactive force acting downwardly on'the member tqmainrtainthe clutch surfaces 22 and 23' engaged during thecontinued upward'movement of the valve toward. closed position.

Figures 3 and 4 illustrate amodifioation'of the invention in which :theannular member 39 functions similarly 'to the previously describedmember l5, "but differs therefrom in that its taperedinternal clutchsurface 3! icoa'cts with a correspondinglytapered clutch surface' tzi.pro-

videdon the lower outer periphery of the valve spring retainer washer33. Adjacent the upper endiof the clutch surface '32-on the retainerwasher is ashouldertfl'which serves as an abutmentiorthe upperend of themembertil in the same manner as described'for the shoulder 24 inthedeviceof Figures land 2. Locating the "clutch surfacei'32 on theretainer washer enables obtaining a larger'mean diameter for thissurfacelthan can conveniently be provided on the "valve stem 35, therebyreducing, the torsional forces on the member 80 inoperation andimproving its general ruggedness to resist strain.

This modification also embodies axdiiferent arrangement from that ofFigures 1 and 2 for effecting a helical interengagement between theannular member and the stationary guide 36.

Instead of counterboring this guide, a ring 37 having one or morenotches 38 in its outer peri phery is fitted over the upper end of theguide and fixedly secured thereto as by welding or other means.Helically inclined arms 59 formed integral with and depending from theannular member slidably engage the respective notches 38' to impartrotation to the membertil as it is driven toward and away from the ring3? with reciprocation of the valve. iil is a longitudinal slit providedin the member 39 to permit its expansion for assembly and disassemblywith the spring retainer washer 33.

Operation of this form of the invention is the same as that previouslydescribed for the device of Figures land 2, differing only in that theforce for rotatingthe valve is applied to the spring retainer washerrather than directly to the valve stem.

.to provide it with an internalclutch surface '56,

equivalent to that designated on annular member--50 previouslydescribed, which coacts with a correspondingly tapered clutch surface 5?on the peripheryrof the valve spring retainer washer 158. [instead of ashoulder being provided as atxtl in Figure 3 forv limiting thegxupwardtravel of the annular; member .56, the upperportion' :is turned.radiallyzinward to; provide it with a shoulder 59 opposite the bottom:end face .Sdof the washer 58, the inner extremity of this shoulderjoining integrally with the upper end of the cylindrical skirt 5!. Aslot- 6! extendingthe fulllength of annularlmember-ill is provided toaccommodate itsexpa-nsion sufficiently at assembly and disassembly'toslip the upperportion 55 thereof over the lower end of the ,vvasher-EE.va

This last described modification .while slightly 7 more expensive toconstruct than that of Figures 3 and 4 has advantageslthereoveriin thatthe annular member 50 is more resistant to torsinal strain whenrotatively driving .the valve during valve. opening by. reason of thestiffening efiect "tact between'its shoulder isxand the bottom end face60 of the washer 58l The similarity of operation iof this forinto -thatf the devices of Figuresl d is believed sufficiently apparent thatfa.'further idescription*islunstem, stationary .guidielzmeans fortherstem, ac-

commodating rotation l "and reciprocation of l the I Valve means, .aspring in abutment with the washer 'anddoiasing the valve meansi'longitudinally of the guide means, and "a valve: operator engageablewiththe stem to move the valve means longitudinally j-againstthejbiasing force of the spring, the combinationtherewith of 'a memberfor rotatingthe valveineans during itslongitudinal movement in onedirection, saidrmember aeoaeoe ber together, said clutch facesterminating atone of their corresponding ends with coacting abutmentslimiting longitudinal movement of the valve means in the oppositedirection relative to the membensaid member having also a helicalinterengagement with the guide means; effective with their relativemovement longitudinally of the guide means in either direction to bothrotate the member and apply a reactive force thereto l longitudinally ofthe valve means, said reactive force serving to hold the clutch surfacesin en- 1 gagement during longitudinalmovement of 'the valve means in thedirection urged by the spring and to hold the clutch surfaces out ofengagement during longitudinal movement of the valve means in theopposite direction by the valve opfor axially reciprocating the valvemeans, the combination therewith of means for rotating the valve meansduring axial movements thereof in one direction, said rotating meanscomprising a member embracing the valve means and provided with aninturned conical clutch face terminating at one of its conical ends withan abutment, a conical clutch face on the valve means terminating at itscorresponding conical end with an abutment cooperable respectively withthe clutch face and abutment of the member in loosely retaining themember on the valve means for reciprocation therewith, said clutch faceswhen engaged being effective to rotatively lock the member and valvemeans together, said member being helically interengaged with the guide.

3. The combination with a valve means mounted for reciprocation to andfrom closed position and for rotation during reciprocation, means forreciprocating said valve means, and guide means for the valve means, ofmeans for causing rotary movement of said valve means duringreciprocation comprising a member having reciprocating movement with thevalve means and a helical connection with the guide means whereby saidmember is caused to rotate alternately in opposite directions relativeto the valve means during reciprocation, and coacting conically shapedclutch faces on the member and valve means for clutching said member tothe valve means during through a lostjmotionconnectiontherewitnsaidconnection beingformed in :part by coacting clutch surfaces onthe memberandstem effective i when engaged both; to .xlimit longitudinal'movementof the memberin oneidirection relative to the stem and torotatively lock the stem and member together; said member having also ahelical int'erengageinent with the guide means effectiveduringxre'ciprocationiofthe member to "eifectrm tation of andapplyreactive. forces to the member in.=alternately' opposite directions,said. reactive forcesmserving. to shift the,1.member*relative to thestem through the range of relative movement provided for byl'said lostmotion connection.

5. The combination with a valve having a stem mounted for-reciprocationto and from closed position and .Ffor rotation duringreciprocation,

:means connected tothe stem for effecting said :reciprocation and-guidemeansifor thestem, of

tmeansfor causing rotary movementof the valve duringlreciprocationcomprising a memberhav- Ling-reciprocating. movement with the valve anda helical connection-with the guide means whererotary movement of saidmember in one direction, said clutch faces terminating at one of theircorresponding ends in coacting abutments having a spaced-apart relationwhen said clutch faces are engaged, said member having a longitudinalslit permitting radial separation of said clutch faces during assemblyand disassembly of the member and valve means.

4. In an internal combustion engine having a poppet valve having a stem,stationary guide means for the stem accommodating rotation andreciprocation of the valve, and means for reciproeating the valve, thecombination therewith of means for rotating the valve duringlongitudinal movement of the stem in one direction including an annularmember loosely surrounding the stem, said member being reciprocated bythe stem by said member is caused to rotate alternately in oppositedirections relative to the valve during reciprocation, and means forclutching said member to the valve stem during rotary movement of themember in one direction.

6. In an internal combustion engine having a poppet valve having a stemwith a valve return spring retaining washer fixed thereto, a guide forthe stem, and means for reciprocating the valve including a springacting against the washer to bias the valve closed, the combinationtherewith of means for rotating the valve during longitudinal movementof the stem inone direction including an annular member coaxial with andconnected to the washer for reciprocation thereby, said connection tothe washer accommodating a predetermined longitudinal movement of thevalve relative to the member of lesser magnitude than the reciprocatorystroke of the valve, said connection including coacting clutch surfaceson the member and washer effective when engaged both to rotatively lookthe member to the washer and to limit longitudinal movement of the valvein one direction relative to the member, said member being alsohelically geared to the guide whereby said member is caused to rotate inalternate directions during reciprocation and said clutch surfaces arebrought into and out of engagement with each other in accordance withthe direction of longitudinal movement of the valve relative to themember.

7. The combination with a valve means including a valve stem and aspring thrust receiving element fixed thereto, guide means for the stemaccommodating reciprocation and rotation of the valve means and meansfor reciprocating the valve means including a spring in thrusttransmitting relation with said element, of means for causing rotarymovement of the valve means during reciprocation comprising a memberhaving reciprocating movement with the valve means and a helicalconnection with the guide means whereby said member is caused to rotatealternately in opposite directions relative to the guide means duringreciprocation, and means for clutching said member to said elementduring rotary movement of the member in one direction.

8. In an internal combustion engine having a poppet valve having a stemwith a valve return spring retaining washer fixed thereto, a guide forthe stem, and means for reciprocating the valv'eincluding a springliacting against the :wash- :er i-toobias :the valve'closedthecombination :there- With of meansifor'rotating the valve during;longi-:tudinal movement o'fxthestem in one direction inicludinga memberhaving: an annular portion-emibracing the washerwand a plurality vofh-elically inclined depending arms, cooperating tapered clutch surfaceson the inner periphery of the annular portion and the outer periphery of:the "washer, said clutch surface on the washerterzminatingupwardly witha shoulder 'inca-butting relation with the uppervend of theannular-portion, and a ring fixedly secured :to the guide havingperipheral slots slidably receiving said arms.

-9. In an internal combustionzengine having a :poppet valvehaving'as'tem with a "valve-return ;spring retaining washer'fixed thereto,'aguide'for .the stem, and V means'iior reciprocating tthe valve includinga spring acting against 'the' washer to :bias the valve closed, 'thecombination therewith of means for rotating the valveIduringlongitudinal movement of therstem :in one directionin- Number.opposite the fiatmortion, ,said cylindrical portion :having .aplurality ofhelical slots in its side wall,

and: pins fixedto theguideand slidably engaging said slots. 7

ROBERT TLDOUGHTY.

v REFERENCESlCITED "The following references are of recordlin "the fileof this patent:

"UNITED STATES PATENTS V y Name a .Date

I 1 ,341,488 7 Arnold v July '27, .1920 1,414,499 Buck May 2, 19221,520,273 Anthony v Dec. '23, -1924 1,610,409

Anthony Dec; 14;, 11926

